ABSTRACT

Lactic Acid Bacteria (Lactobacillus acidophilus, Lactobacillus plantarium, and Bifidobacterium) isolated from fermented Ogi and Breast milk using MRS agar medium and a commercially acquired lactic acid bacteria (LAB) were used to produce yoghurt samples. Fermented Ogi and breast-milk samples was appropriately diluted and plated out on the MRS Agar using pour plate method. The plates were incubated under 35oC-37oC and at different pH for 48 hours under Micro aerophilic condition using excello anaerobic jar. The effect of varied temperature and pH on the growth of the isolates was investigated to determine the optimum temperature and pH for the growth of the organism. The isolates and the commercially acquired Lactic acid bacteria were used to produce Yoghurt samples A-D from DANO powdered milk in an 8 hours fermentation process. The fermented product was used to compare favourably against the commercial product in terms of both nutritional and sensory attributes. The three LAB isolates were used singly as starter culture. The optimum pH for the Yoghurt production was 5.5 while the optimum temperature is 40oC. The Yoghurt sample C had the highest pH (6.60 ± 0.00; p<0.05) and highest moisture content (88.10 ± 0.04; p<0.05), the highest protein content was from sample A and D (control). Sample A has the highest crude fat (0.85 ± 0.00; p<0.05) ash content was highest in sample D (control) (3.29 ± 0.05; p<0.05) and the fibre content of the Yoghurt was: 0.14 ± 0.02; p<0.05. It was therefore concluded that L. acidophilus, L. plantarium and Bifidobacterium can be used in Yoghurt production as a starter culture which are sourced from breast-milk and fermented Ogi. However, Bifidobacterium are more suitable for use as starter culture than the others.